Nuclear Medicine & Radioisotope Technologies

1896 · 130 years ago

Wilhelm Röntgen discovered X-rays

Within months of the discovery, physicians in Europe and the US were using X-rays experimentally against tumours, and Röntgen's finding founded both diagnostic radiology and, alongside the Curies' work, the practice of radiation therapy.

1896 · 130 years ago

Henri Becquerel discovered radioactivity

Becquerel's identification of radioactivity in uranium salts established the physical phenomenon on which all later nuclear medicine rested. Together with Roentgen's X-rays and Marie Curie's work on thorium and polonium, it formed the scientific foundation of medical radiation use.

1898 · 128 years ago

Marie and Pierre Curie discovered radium and polonium

Their isolation of intensely radioactive elements from pitchblende ore led within a few years to radium being used to treat tumours, founding the practice of radiotherapy and earning Marie Curie two Nobel Prizes in different sciences.

• Marie Curie died from illness linked to decades of radiation exposure

1925 · 101 years ago

George de Hevesy performed the first radioactive tracer study in animals

De Hevesy's animal tracer experiment demonstrated that radioactive substances could be followed through a living organism. This tracer principle became the conceptual core of diagnostic nuclear medicine.

1926 · 100 years ago

Herman Blumgart and Otto Yens performed the first diagnostic tracer study in humans

A year after de Hevesy's animal work, Blumgart and Yens applied the tracer method to human subjects. This marked the first diagnostic use of radioactivity inside the human body.

1930s · 96 years ago

Taro Takemi studied the application of nuclear physics to medicine

Takemi was among the early pioneers exploring how nuclear physics could serve medical purposes. His work forms part of the interdisciplinary origins of the specialty.

February 1934 · 92 years ago

Frédéric and Irène Joliot-Curie reported the first artificial production of radioactive material in Nature

After detecting radioactivity in polonium-irradiated aluminium foil, the Joliot-Curies announced artificially produced radionuclides. Many historians regard this as the single most significant milestone in nuclear medicine, as it opened the way to purpose-made medical radionuclides.

1936 · 90 years ago

John Lawrence visited his brother's Berkeley radiation laboratory

Lawrence, later called the father of nuclear medicine, took leave from Yale Medical School to work at Ernest Lawrence's new radiation laboratory in California. He subsequently made the first application in patients of an artificial radionuclide, using phosphorus-32 to treat leukaemia.

1937 · 89 years ago

C. Perrier and E. Segre discovered technetium-99m as an artificial element

Technetium was created to fill element 43 in the periodic table. It later became the most widely used radionuclide in nuclear medicine imaging.

1941 · 85 years ago

Saul Hertz used radioactive iodine to treat a thyroid patient for the first time

Hertz's treatment, developed with physicist Arthur Roberts at MIT, exploited the thyroid's natural uptake of iodine to deliver radiation directly to the gland, the first targeted radionuclide therapy and a model for later theranostic treatments.

1946 · 80 years ago

The US Atomic Energy Commission began distributing reactor-produced radioisotopes for civilian medical use

Isotopes from the Oak Ridge reactor, previously produced only for weapons research, became available to hospitals and researchers through US Atomic Energy Commission distribution, giving clinicians a reliable supply of medical radionuclides and launching mass production of the radioactive materials that modern nuclear medicine depends on. Historians often place the birth of nuclear medicine between the 1934 discovery of artificial radioactivity and this event.

May 1946 · 80 years ago

Saul Hertz and Arthur Roberts published the successful treatment of Graves' disease with radioactive iodine

Their JAMA article described therapeutic use of radioiodine for thyroid disease, and is considered among the most important papers in the field. Sam Seidlin's report of successful radioiodine treatment of thyroid cancer metastases added further momentum, giving nuclear medicine public recognition as a potential specialty.

1950s · 76 years ago

Benedict Cassen developed the first imaging with a rectilinear scanner

Cassen's work with a directional probe led to the first nuclear imaging device capable of mapping radioactivity distribution. Gordon Brownell separately developed the first positron scanner in the same period.

early 1950s · 76 years ago

Nuclear medicine entered widespread clinical use

Expanding knowledge of radionuclides, radiation detection and biochemical tracing brought nuclear medicine into routine clinical practice. Early applications included therapy of haematological malignancies and of benign and malignant thyroid disease.

late 1950s · 76 years ago

David E. Kuhl and Roy Edwards introduced the concept of emission and transmission tomography

Their concept later developed into single photon emission computed tomography and led to several tomographic instruments built at the University of Pennsylvania. Techniques were developed further at Washington University School of Medicine.

1950s · 76 years ago

Solomon Berson and Rosalyn Yalow developed radioimmunoassay

Radioimmunoassay used radioactive labelling to measure minute quantities of biological substances and was applied extensively in clinical medicine. Yalow received a share of the 1977 Nobel Prize in Physiology or Medicine for the work; it has since been largely replaced by non-radioactive methods.

1951 · 75 years ago

Harold Johns built the first cobalt-60 teletherapy machine

The Canadian physicist's device, first used to treat a patient in Saskatchewan, delivered high-energy gamma radiation from a sealed radioactive source and became the standard external beam radiotherapy machine worldwide until linear accelerators largely replaced it decades later.

1953 · 73 years ago

Stanford University physicians treated the first patient with a medical linear accelerator

The machine used microwave technology developed for wartime radar to accelerate electrons and generate high-energy X-rays for cancer treatment, establishing the technology that eventually displaced cobalt units as the mainstay of radiotherapy.

1954 · 72 years ago

Society of Nuclear Medicine was organised in Spokane, Washington

The founding of the SNM gave the emerging discipline a professional institution. It helped consolidate standards and identity for practitioners across physics, chemistry and medicine.

1958 · 68 years ago

Hal Anger developed the gamma scintillation camera

The Anger camera could image an entire region simultaneously rather than scanning point by point. It transformed nuclear medicine into a full-fledged medical imaging specialty.

1960 · 66 years ago

Researchers at Brookhaven National Laboratory developed the technetium-99m generator

The device let hospitals produce a short-lived isotope on-site from a longer-lived parent, and technetium-99m went on to become the workhorse of diagnostic nuclear medicine, used in the large majority of imaging procedures worldwide.

early 1960s · 66 years ago

Niels A. Lassen, David H. Ingvar and Erik Skinhøj produced the first blood flow maps of the brain

Working in southern Scandinavia, they used xenon-133 inhalation and later intra-arterial methods to measure local cerebral activity. Later versions with 254 scintillators produced two-dimensional images of brain activation during speech, reading, perception and movement, opening functional brain imaging.

early 21st century

Health authorities approved medical reimbursement of PET and PET/CT in oncology

PET had grown slowly because of its cost and the need for a nearby cyclotron. An administrative reimbursement decision, alongside 18F-labelled tracers usable at non-cyclotron sites, drove rapid growth and widespread clinical acceptance.

Early 2026 · 6 months ago

NTP Radioisotopes expanded production capacity at its South African facility

The state-owned company, one of a handful of global suppliers of molybdenum-99 for diagnostic imaging, continued investing in production capacity as demand for nuclear medicine procedures grew across lower-income countries acquiring imaging equipment for the first time.

March 2025 · last year

Novartis won approval to use Pluvicto earlier in prostate cancer treatment

US regulators expanded approval of the lutetium-177 radioligand therapy to patients who had not yet received chemotherapy, broadening the eligible patient population for a treatment that delivers targeted radiation directly to cancer cells expressing a prostate-specific protein.

• The therapy's cost remained a barrier to access outside wealthy health systems

2025 · last year

Argentina's INVAP continued marketing its research reactor and isotope technology internationally

Building on earlier projects including Australia's OPAL reactor, the state nuclear engineering firm pursued further contracts to build research reactors and isotope production facilities for countries seeking to develop their own nuclear medicine supply chains.

2025 · last year

The IAEA's Rays of Hope initiative delivered radiotherapy equipment to African countries that had previously had none

The programme, aimed at closing a stark gap in cancer treatment access, continued installing linear accelerators and training staff in countries where patients had previously had to travel abroad, sometimes at prohibitive cost, for radiotherapy.

• Sub-Saharan Africa still had only a small fraction of the radiotherapy machines recommended for its cancer burden

2025 · last year

India's Board of Radiation and Isotope Technology scaled up domestic production of lutetium-177

Expanded domestic output aimed to lower the cost of radioligand cancer therapy for Indian patients, reducing reliance on imported isotope supply and supporting a growing number of nuclear medicine centres across the country.

2025 · last year

SHINE Technologies began supplying domestically produced molybdenum-99 to US hospitals

The Wisconsin company's fusion-driven production method, an alternative to the ageing research reactors most global supply has relied on, became one of the first new US sources of the isotope in decades, easing a supply chain long dependent on imports.

• Global molybdenum-99 supply had long depended on a small number of ageing reactors prone to shutdowns

2024 · 2 years ago

Saudi Arabia and the UAE invested in proton beam therapy infrastructure

Gulf states expanded cancer treatment capacity as part of broader healthcare diversification plans, adding proton therapy centres intended to reduce the number of patients travelling abroad for advanced radiation treatment and to build regional medical capacity.

2024 · 2 years ago

The IAEA continued helping countries replace high-activity cobalt-60 radiotherapy units with linear accelerators

Older cobalt teletherapy machines, still in use in parts of the developing world, pose a theft and radiological security risk that newer electrically powered linear accelerators avoid, and the agency's replacement programme continued alongside its broader source security work.

2024 · 2 years ago

The Netherlands advanced construction preparations for the Pallas research reactor

Intended to replace the ageing HFR Petten reactor as a mainstay of European medical isotope supply, the project continued moving through licensing and site works after years of delay, with European hospitals still dependent on a handful of ageing reactors.

2024 · 2 years ago

China pushed to reduce reliance on imported medical isotopes

State nuclear companies expanded domestic production of molybdenum-99 and other diagnostic and therapeutic isotopes, part of a broader strategy to secure supply for a rapidly growing number of hospitals offering nuclear medicine and radiotherapy services.

2018 · 8 years ago

Chalk River Laboratories was permanently shut down

The Ontario facility had produced roughly a third of the world's radionuclide supply and most of North America's. Its closure removed a major source of medical isotopes.

2018 · 8 years ago

Advanced Accelerator Applications won approval for the first peptide receptor radionuclide therapy

Lutathera, a lutetium-177-labelled peptide developed from research pioneered in Rotterdam, delivered targeted radiation to neuroendocrine tumours by binding to receptors on cancer cells, establishing the theranostic approach later extended to prostate cancer with Pluvicto.

2011 · 15 years ago

Manufacturers brought a fully integrated MRI/PET scanner to market

Combining magnetic resonance and positron emission imaging in one device extended hybrid imaging beyond PET/CT. It marked the latest stage in multimodal molecular imaging.

1998 · 28 years ago

D. W. Townsend built the first PET/CT prototype

Working at the University of Pittsburgh, Townsend combined positron emission and computed tomography in one instrument, following earlier SPECT/CT fusion imaging by Bruce Hasegawa at UCSF. PET/CT became integral to oncological diagnosis, staging and treatment monitoring.

1994 · 32 years ago

Radiation oncologists developed intensity-modulated radiotherapy

Using computer-controlled multileaf collimators to shape radiation dose around a tumour's exact geometry, IMRT let clinicians deliver higher doses to cancer while sparing more surrounding healthy tissue than earlier external beam techniques allowed.

1980s · 46 years ago

Radiopharmaceutical developers designed agents for diagnosis of heart disease

New radiopharmaceuticals targeted cardiac diagnosis, and the near-simultaneous arrival of SPECT allowed three-dimensional reconstruction of the heart. Together these established the field of nuclear cardiology.

1974 · 52 years ago

American Osteopathic Board of Nuclear Medicine was established

Its creation extended formal nuclear medicine certification to osteopathic physicians. This completed the institutional framework confirming the field as a distinct specialty.

1973 · 53 years ago

Michael Phelps and Edward Hoffman developed the first positron emission tomography scanner

PET imaging used radiation from positron-emitting isotopes to map metabolic activity in the body, later becoming essential for cancer staging and, combined with CT scanning, one of the most widely used imaging techniques in oncology.

1972 · 54 years ago

American Board of Nuclear Medicine was established

The board created formal certification for nuclear medicine physicians in the United States. Together with the American Osteopathic Board of Nuclear Medicine in 1974, it cemented nuclear medicine as a stand-alone specialty.

1971 · 55 years ago

American Medical Association officially recognised nuclear medicine as a medical specialty

By the 1970s most organs could be visualised using nuclear medicine procedures, and formal recognition followed. It established the discipline's professional standing in the United States.